Bluedio R2 Wireless Bluetooth Stereo Headphones/Headset HiFi Rank 8 Drivers Support Line-in Mode Multi-media Playing(Black) 8 driver units deliver deep, powerful sound, which is composed of 2 woofers (50mm 50) and 6 3D speakers (13mm 32). Thanks to Bluetooth 4.0 low energy technology.Bluedio R2 Bluetooth headset has up to 1300hrs ultra-long standby time and up to 20hrs Bluetooth music playtime. Soft earcups, lightweigth guarantees long-wearing comfort.Also R2 support many music formats such as FLAC/WAV/AAC and APE. If the battery runs out, you can still enjoy music with included aux cable plugged in. Built-in Mic for handsfree phone calls